1 /* 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Scooter Morris at Genentech Inc. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)lockf.h 8.1 (Berkeley) 6/11/93 37 * $FreeBSD: src/sys/sys/lockf.h,v 1.10 1999/08/28 00:51:51 peter Exp $ 38 * $DragonFly: src/sys/sys/lockf.h,v 1.3 2003/08/20 07:31:21 rob Exp $ 39 */ 40 41 #ifndef _SYS_LOCKF_H_ 42 #define _SYS_LOCKF_H_ 43 44 #include <sys/queue.h> 45 46 struct vop_advlock_args; 47 48 /* 49 * The lockf structure is a kernel structure which contains the information 50 * associated with a byte range lock. The lockf structures are linked into 51 * the inode structure. Locks are sorted by the starting byte of the lock for 52 * efficiency. 53 */ 54 TAILQ_HEAD(locklist, lockf); 55 56 struct lockf { 57 short lf_flags; /* Semantics: F_POSIX, F_FLOCK, F_WAIT */ 58 short lf_type; /* Lock type: F_RDLCK, F_WRLCK */ 59 off_t lf_start; /* Byte # of the start of the lock */ 60 off_t lf_end; /* Byte # of the end of the lock (-1=EOF) */ 61 caddr_t lf_id; /* Id of the resource holding the lock */ 62 struct lockf **lf_head; /* Back pointer to the head of the locf list */ 63 struct inode *lf_inode; /* Back pointer to the inode */ 64 struct lockf *lf_next; /* Pointer to the next lock on this inode */ 65 struct locklist lf_blkhd; /* List of requests blocked on this lock */ 66 TAILQ_ENTRY(lockf) lf_block;/* A request waiting for a lock */ 67 }; 68 69 /* Maximum length of sleep chains to traverse to try and detect deadlock. */ 70 #define MAXDEPTH 50 71 72 int lf_advlock (struct vop_advlock_args *, struct lockf **, u_quad_t); 73 74 #ifdef LOCKF_DEBUG 75 void lf_print (char *, struct lockf *); 76 void lf_printlist (char *, struct lockf *); 77 #endif 78 79 #endif /* !_SYS_LOCKF_H_ */ 80